Method for manufacturing thin-film transistor substrate and thin-film transistor substrate manufactured with same

ABSTRACT

The present invention provides a method for manufacturing a thin-film transistor substrate and a thin-film transistor substrate manufactured with the method. The method includes: (1) providing a substrate ( 20 ); (2) forming a gate terminal ( 22 ) having a predetermined structure on the substrate ( 20 ); (3) forming a gate insulation layer ( 24 ) on the gate terminal ( 22 ) and the substrate ( 20 ); (4) forming a metal signal line ( 26 ) having a predetermined structure on the gate insulation layer ( 24 ); (5) forming an oxide semiconductor layer ( 28 ) having a predetermined structure on the gate insulation layer ( 24 ); (6) forming a passivation layer ( 32 ) having a predetermined structure on the gate insulation layer ( 24 ), the metal signal line ( 26 ), and the oxide semiconductor layer ( 28 ); and (7) forming a source/drain terminal ( 34 ) having a predetermined structure on the metal signal line ( 26 ), the oxide semiconductor layer ( 28 ), and the passivation layer ( 32 ) so as to form a thin-film transistor substrate.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of liquid crystal displaying,and in particular to a method for manufacturing a thin-film transistor(TFT) substrate and a thin-film transistor substrate manufactured withthe method.

2. The Related Arts

A thin-film transistor (TFT) has been widely used in electronic devicesto serve as a switching device and a driving device. Specifically, thethin-film transistors can be formed on a glass substrate or a plasticsubstrate so that they are commonly used in the field of flat paneldisplay devices, such as a liquid crystal display (LCD), an organiclight-emitting display (OLED), and an electro-phoretic display (EPD).

Oxide semiconductors have a relatively high electron mobility (theelectron mobility of oxide semiconductors >10 cm²/Vs, while the mobilityof a-Si being only 0.5-0.8 cm²/Vs) and, compared to low temperaturepoly-silicon (LTPS), the oxide semiconductors have a simplemanufacturing process, are highly compatible with a-Si manufacturingprocesses, are applicable to the fields of LCDs, OLEDs, and flexibledisplays, and are compatible to high generation manufacturing lines forapplications to displays of large, medium, and small sizes, so as have aprosperous future of applications and be a hot spot of researches of theindustry. Among the studies of the oxide semiconductors, InGaZnO (IGZO)semiconductors are the most developed one.

A thin-film transistor substrate comprises thin-film transistors andpixel electrodes. For a conventional oxide semiconductor thin-filmtransistor substrate, as shown in FIG. 1, after an oxide semiconductorlayer 100 has been formed, a metal source/drain electrode 200 must beformed. The metal source/drain electrode 200 uses a wet etching process,which often uses strong acids and mixtures thereof (such asHNO₃/H₃PO₄/CH₃COOH) that readily cause damages of the oxidesemiconductor of a back channel etching site. Using a dry etchingprocess instead, however, causes problems of poor uniformity of etching.To dissolve such a problem, the known techniques often form an etch-stoplayer (ESL) 300 after the formation of the oxide semiconductor layer 100and before the formation of the metal source/drain electrode 200 inorder to protect the oxide semiconductor layer of the back channeletching site for preventing damage caused in the processes of forexample etching of metal source/drain electrode 200. However, formingthe additional etch-stop layer requires an additional photolithographicprocess. The photolithographic process comprises various operations,such as film forming, exposure, development, etching, and peeling, sothat forming such an additional etch-stop layer would greatly increasethe manufacture cost and lower down yield rate.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a method formanufacturing a thin-film transistor substrate, which can effectiveavoid damages of an oxide semiconductor layer caused by etchingprocesses of metal signal lines and source/drain electrodes, enhancestability and uniformity of thin-film transistor substrates, improveyield rate, expand the likelihood of mass production of oxidesemiconductor thin-film transistor substrate, and can reduce one roundof photolithographic process to thereby greatly lower down themanufacture cost and improve manufacture yield rate.

Another object of the present invention is to provide a thin-filmtransistor substrate, which has a simple structure, possesses enhancedstability and uniformity, has a simple manufacturing process, and canreduce one round of photolithographic process to thereby greatly lowerdown the manufacture cost and improve manufacture yield rate.

To achieve the above objects, the present invention provides a methodfor manufacturing a thin-film transistor substrate, which comprises thefollowing steps:

(1) providing a substrate;

(2) forming a gate terminal having a predetermined structure on thesubstrate;

(3) forming a gate insulation layer on the gate terminal and thesubstrate;

(4) forming a metal signal line having a predetermined structure on thegate insulation layer;

(5) forming an oxide semiconductor layer having a predeterminedstructure on the gate insulation layer;

(6) forming a passivation layer having a predetermined structure on thegate insulation layer, the metal signal line, and the oxidesemiconductor layer; and

(7) forming a source/drain terminal having a predetermined structure onthe metal signal line, the oxide semiconductor layer, and thepassivation layer so as to form a thin-film transistor substrate.

The substrate is a glass substrate; the oxide semiconductor layer isformed of indium gallium zinc oxide, indium gallium oxide, zinc oxide,aluminum oxide, or tin oxide.

In step (6), at the same time when the passivation layer is formed, anetch-stop layer having a predetermined structure is also formed, theetch-stop layer being located on the oxide semiconductor layer thepassivation layer being arranged at opposite sides of the etch-stoplayer, the passivation layer and the etch-stop layer being made of thesame material or different materials.

In step (7), at the same time when the source/drain terminal is formed,a pixel electrode is also formed, the pixel electrode being formed onthe passivation layer and electrically connected with the source/drainterminal, the source/drain terminal and the pixel electrode being bothformed of transparent conductive oxide.

The transparent conductive oxide comprises indium tin oxide.

The present invention also provides a method for manufacturing athin-film transistor substrate, which comprises the following steps:

(1) providing a substrate;

(2) forming a gate terminal having a predetermined structure on thesubstrate;

(3) forming a gate insulation layer on the gate terminal and thesubstrate;

(4) forming a metal signal line having a predetermined structure on thegate insulation layer;

(5) forming an oxide semiconductor layer having a predeterminedstructure on the gate insulation layer;

(6) forming a passivation layer having a predetermined structure on thegate insulation layer, the metal signal line, and the oxidesemiconductor layer; and

(7) forming a source/drain terminal having a predetermined structure onthe metal signal line, the oxide semiconductor layer, and thepassivation layer so as to form a thin-film transistor substrate;

wherein in step (6), at the same time when the passivation layer isformed, an etch-stop layer having a predetermined structure is alsoformed, the etch-stop layer being located on the oxide semiconductorlayer the passivation layer being arranged at opposite sides of theetch-stop layer, the passivation layer and the etch-stop layer beingmade of the same material or different materials.

The substrate is a glass substrate; the oxide semiconductor layer isformed of indium gallium zinc oxide, indium gallium oxide, zinc oxide,aluminum oxide, or tin oxide.

In step (7), at the same time when the source/drain terminal is formed,a pixel electrode is also formed, the pixel electrode being formed onthe passivation layer and electrically connected with the source/drainterminal, the source/drain terminal and the pixel electrode being bothformed of transparent conductive oxide.

The transparent conductive oxide comprises indium tin oxide.

The present invention further provides a thin-film transistor substrate,which comprises:

a substrate;

a gate terminal, which is located on the substrate;

a gate insulation layer, which is located on the substrate and the gateterminal;

a metal signal line, which is located on the gate insulation layer;

an oxide semiconductor layer, which is located on the gate insulationlayer and arranged at one side of the metal signal line;

a passivation layer, which is located on the gate insulation layer, themetal signal line, and the oxide semiconductor layer;

a source/drain terminal, which is located on the metal signal line, theoxide semiconductor layer, and the passivation layer, the source/drainterminal being electrically connected with the metal signal line; and

a pixel electrode, which is located on the passivation layer and is indirect contact with the source/drain terminal, and is located on thesame layer as the source/drain terminal, the source/drain terminal andthe pixel electrode being formed of transparent conductive oxide.

The substrate is a glass substrate.

The oxide semiconductor layer is formed of indium gallium zinc oxide,indium gallium oxide, zinc oxide, aluminum oxide, or tin oxide.

Thin-film transistor substrate further comprises an etch-stop layerlocated on the oxide semiconductor layer. The etch-stop layer and thepassivation layer are formed at the same time and are made of the samematerial or different materials.

The source/drain terminal and the pixel electrode are formed at the sametime and the transparent conductive oxide is indium tin oxide.

The efficacy of the present invention is that the present inventionprovides a method for manufacturing a thin-film transistor substrate anda thin-film transistor substrate manufactured with the method, whereinan oxide semiconductor layer is formed after a metal signal line andfurther, an etch-stop layer is manufactured before formation of asource/drain terminal, and a transparent conductive oxide (TCO) is usedto replace the conventional material for manufacturing the source/drainterminal in order to avoid damages of the oxide semiconductor layercaused by etching processes of the metal signal line and thesource/drain terminal, thereby enhancing stability and uniformity of thethin-film transistor substrate, improving manufacture yield rate, andexpanding the likelihood of mass production of the oxide semiconductorthin-film transistor substrate. Further, the etch-stop layer and thepassivation layer are formed on the same layer and the source/drainelectrode and the pixel electrode are formed on the same layer so thatthe number of layers made is reduced by one and one round ofphotolithographic process (which comprises operations of film forming,exposure, development, etching, and peeling) is reduced so as to greatlylower down the manufacture cost and improve manufacture yield rate.

For better understanding of the features and technical contents of thepresent invention, reference will be made to the following detaileddescription of the present invention and the attached drawings. However,the drawings are provided for the purposes of reference and illustrationand are not intended to impose limitations to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The technical solution, as well as other beneficial advantages, of thepresent invention will be apparent from the following detaileddescription of embodiments of the present invention, with reference tothe attached drawing. In the drawing:

FIG. 1 is a schematic view showing the structure of a conventionalthin-film transistor substrate;

FIG. 2 is a flow chart illustrating a method for manufacturing athin-film transistor substrate according to the present invention;

FIGS. 3-8 are schematic views illustrating a process of manufacturing athin-film transistor substrate by using the method for manufacturing athin-film transistor substrate according to an embodiment of the presentinvention;

FIGS. 9-14 are schematic views illustrating a process of manufacturing athin-film transistor substrate by using the method for manufacturing athin-film transistor substrate according to another embodiment thepresent invention;

FIG. 15 is a schematic view showing the structure of a thin-filmtransistor substrate according an embodiment of the present invention;and

FIG. 16 is a schematic view showing the structure of a thin-filmtransistor substrate according another embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

To further expound the technical solution adopted in the presentinvention and the advantages thereof, a detailed description is given toa preferred embodiment of the present invention and the attacheddrawings.

Referring to FIG. 2, with additional reference had to FIGS. 3-8, thepresent invention provides a method for manufacturing a thin-filmtransistor substrate, which comprises the following steps:

Step 1: providing a substrate 20.

The substrate 20 is a transparent substrate, preferably a glasssubstrate or a plastic substrate. In the instant embodiment, thesubstrate 20 is a glass substrate.

Step 2: forming a gate terminal 22 having a predetermined structure onthe substrate 20.

A first-round photolithographic process is applied to form the gateterminal 22 having the predetermined structure on the substrate 20 andthe specific processing flow includes: first depositing a first metallayer on the substrate 20 and then applying a mask or a halftone mask tosubject the first metal layer to exposure, development, and etching soas to form the predetermined structure of the gate terminal 22, therebycompleting the first-round photolithographic process. The first metallayer is generally one of an aluminum layer, a copper layer, and amolybdenum layer or a combination thereof.

Step 3: forming a gate insulation layer 24 on the gate terminal 22 andthe substrate 20.

A second-round photolithographic process is applied to form the gateinsulation layer 24 on the gate terminal 22 and the substrate 20. Thegate insulation layer 24 generally comprises one of silicon oxide andsilicon nitride or a combination thereof and is formed in a way similarto that of the above described gate terminal 22 so that repeateddescription will be omitted.

Step 4: forming a metal signal line 26 having a predetermined structureon the gate insulation layer 24.

A third-round photolithographic process is applied to form the metalsignal line 26 having the predetermined structure on the gate insulationlayer 24 and the specific processing flow includes: depositing a secondmetal layer on the gate insulation layer 24 and then applying a mask ora halftone mask to subject the second metal layer to exposure,development, and etching so as to form the predetermined structure ofthe metal signal line 26.

The second metal layer is generally one of an aluminum layer, a copperlayer, and a molybdenum layer or a combination thereof.

Step 5: forming an oxide semiconductor layer 28 having a predeterminedstructure on the gate insulation layer 24.

A fourth-round photolithographic process is applied to form the oxidesemiconductor layer 28 having the predetermined structure on the gateinsulation layer 24 and the way of formation is similar to that of theabove described gate terminal 22 or metal signal line 26 so thatrepeated description will be omitted.

The oxide semiconductor layer 28 can be one of an indium gallium zincoxide (IGZO) semiconductor layer, an indium gallium oxide semiconductorlayer, a zinc oxide semiconductor layer, an aluminum oxide semiconductorlayer, and a tin oxide semiconductor layer and is preferably an indiumgallium zinc oxide semiconductor layer. The oxide semiconductor layer 28is located at one side of the metal signal line 26 and preferably, theoxide semiconductor layer 28 and the metal signal line 26 are shiftedfrom each other in a horizontal direction.

The oxide semiconductor layer 28 is manufactured after the formation ofthe metal signal line 26 so as to avoid damages of the oxidesemiconductor layer caused by the etching operation of the metal signalline 26 so as to enhance the stability and uniformity of the thin-filmtransistor substrate, improve manufacture yield rate, and expand thelikelihood of mass production of the oxide semiconductor thin-filmtransistor substrate.

Step 6: forming a passivation layer 32 having a predetermined structureon the gate insulation layer 24, the metal signal line 26, and the oxidesemiconductor layer 28.

A fifth-round photolithographic process is applied to form thepassivation layer 32 having the predetermined structure on the gateinsulation layer 24, the metal signal line 26, the oxide semiconductorlayer 28. The way of forming passivation layer 32 is similar to that ofthe above described gate terminal 22 or metal signal line 26 so thatrepeated description will be omitted.

It is noted that after the passivation layer 32 is formed on the metalsignal line 26, a portion of the passivation layer 32 that correspondsto the metal signal line 26 must be etched off in order to form acontact hole for exposing the metal signal line 26, allowing forelectrical connection of a source/drain terminal 34 that is formed afterthe formation of the passivation layer 32 with the metal signal line 26.The etching operation used can be a dry etching process or a wet etchingprocess.

Step 7: forming a source/drain terminal 34 having a predeterminedstructure on the metal signal line 26, the oxide semiconductor layer 28,and the passivation layer 32 so as to form a thin-film transistorsubstrate.

In Step 7, at the same time when the source/drain terminal 34 is formed,a pixel electrode 36 is also formed. The pixel electrode 36 is formed onthe passivation layer 32 and is electrically connected to thesource/drain terminal 34. The source/drain terminal 34 and the pixelelectrode 36 are both formed of a transparent conductive oxide (TCO). Inthe instant embodiment, the transparent conductive oxide is preferablyindium tin oxide.

The source/drain terminal 34 and the pixel electrode 36 are formed in away similar to the above described gate terminal 22 or metal signal line26 so that repeated description will be omitted.

It is noted that the thin-film transistor substrate according to thepresent invention can be applied to various fields including a liquidcrystal display (LCD), an organic light-emitting display (OLED), and anelectro-phoretic display (EPD) and can be used in the field of activedisplaying applications, including both non-flexible and flexibledisplays, and can be used in displays of large, medium, and small sizes.

Referring to FIGS. 9-14, with additional reference to FIG. 16, schematicviews illustrating a process of manufacturing a thin-film transistorsubstrate by using the method for manufacturing a thin-film transistorsubstrate according to another embodiment the present invention aregiven. In the instant embodiment, Steps 1-5 and Step 7 are identical tocounterpart steps of the previous embodiment and a difference resides inStep 6. In Step 6 of the instant embodiment, at the same time when thepassivation layer 32 is formed, an etch-stop layer 30 having apredetermined structure is also formed. The etch-stop layer 30 islocated on the oxide semiconductor layer 28, while the passivation layer32 is located on opposite sides of the etch-stop layer 30. Thepassivation layer 32 and the etch-stop layer 30 can be made of the samematerial or they can be made of different materials. In the instantembodiment, the passivation layer 32 and the etch-stop layer 30 are madeof the same material.

The etch-stop layer 30 is provided to protect the oxide semiconductorlayer 28 at a back channel etching site to avoid of damages causedthereon by a process of etching of the source/drain terminal 34.

In the instant embodiment, the etch-stop layer 30 and the passivationlayer 32 are formed as the same layer so that the number of layersmanufactured can be reduced by one. In other words, one round ofphotolithographic process (which comprises operations of film forming,exposure, development, etching, and peeling) can be reduced so as togreatly lower down the manufacture cost and improve manufacture yieldrate.

Referring to FIG. 15, the present invention also provides a thin-filmtransistor substrate, which comprises: a substrate 20, a gate terminal22, a gate insulation layer 24, a metal signal line 26, an oxidesemiconductor layer 28, a passivation layer 32, a source/drain terminal34, and a pixel electrode 36.

The substrate 20 is a transparent substrate, preferably a glasssubstrate or a plastic substrate. In the instant embodiment, thesubstrate 20 is a glass substrate.

The gate terminal 22 is located on the substrate 20. The specificprocess for forming the gate terminal 22 on the substrate 20 includes:first depositing a first metal layer on the substrate 20 and thenapplying a mask or a halftone mask to subject the first metal layer toexposure, development, and etching so as to form the predeterminedstructure of the gate terminal 22. The first metal layer is generallyone of an aluminum layer, a copper layer, and a molybdenum layer or acombination thereof.

The gate insulation layer 24 is located on the substrate 20 and the gateterminal 22. The gate insulation layer 24 generally comprises one ofsilicon oxide and silicon nitride or a combination thereof.

The metal signal line 26 is located on the gate insulation layer 24. Themanufacturing process of the metal signal line 26 includes: depositing asecond metal layer on the gate insulation layer 24 and then applying amask or a halftone mask to subject the second metal layer to exposure,development, and etching so as to form the predetermined structure ofthe metal signal line 26. The second metal layer is generally one of analuminum layer, a copper layer, and a molybdenum layer or a combinationthereof.

The metal signal line 26 is manufactured before the formation of theoxide semiconductor layer 28 so as to avoid damages of the oxidesemiconductor layer caused by the etching operation of the metal signalline 26 so as to enhance the stability and uniformity of the thin-filmtransistor substrate, improve manufacture yield rate, and expand thelikelihood of mass production of the oxide semiconductor thin-filmtransistor substrate.

The oxide semiconductor layer 28 is located on the gate insulation layer24 and is arranged at one side of the metal signal line 26. The oxidesemiconductor layer 28 is an indium gallium zinc oxide semiconductorlayer (IGZO) and preferably, the oxide semiconductor layer 28 and themetal signal line 26 are shifted from each other in a horizontaldirection.

The passivation layer 32 is located on the gate insulation layer 24, themetal signal line 26, and the oxide semiconductor layer 28.

The source/drain terminal 34 is located on the metal signal line 26, theoxide semiconductor layer 28, and the passivation layer 32 and thesource/drain terminal 34 is electrically connected to the metal signalline 26.

The pixel electrode 36 is located on the passivation layer 32 and is indirect contact with the source/drain terminal 34 and is located on thesame layer as the source/drain terminal 34. The source/drain terminal 34and the pixel electrode 36 are formed at the same time.

The source/drain terminal 34 and the pixel electrode 36 are both formedof a transparent conductive oxide (TCO). In the instant embodiment, thetransparent conductive oxide (TCO) is indium tin oxide.

Referring to FIG. 16, which is a schematic view showing the structure ofa thin-film transistor substrate according another embodiment of thepresent invention, in the instant embodiment, the thin-film transistorsubstrate further comprises an etch-stop layer 30. The etch-stop layer30 is located on the oxide semiconductor layer 28. The etch-stop layer30 is provided to protect the oxide semiconductor layer 28 at a backchannel etching site to avoid of damages caused thereon by a process ofetching of the source/drain terminal 34.

The passivation layer 32 is located on opposite sides of the etch-stoplayer 30. The passivation layer 32 and the etch-stop layer 30 arelocated on the same layer and are formed at the same time. Thepassivation layer 32 and the etch-stop layer 30 can be made of the samematerial or they can be made of different materials. In the instantembodiment, the passivation layer 32 and the etch-stop layer 30 are madeof the same material.

In the instant embodiment, the etch-stop layer 30 and the passivationlayer 32 are formed as the same layer so that the number of layersmanufactured can be reduced by one. In other words, one round ofphotolithographic process (which comprises operations of film forming,exposure, development, etching, and peeling) can be reduced so as togreatly lower down the manufacture cost and improve manufacture yieldrate.

In summary, the present invention provides a method for manufacturing athin-film transistor substrate and a thin-film transistor substratemanufactured with the method, wherein an oxide semiconductor layer isformed after a metal signal line and further, an etch-stop layer ismanufactured before formation of a source/drain terminal, and atransparent conductive oxide (TCO) is used to replace the conventionalmaterial for manufacturing the source/drain terminal in order to avoiddamages of the oxide semiconductor layer caused by etching processes ofthe metal signal line and the source/drain terminal, thereby enhancingstability and uniformity of the thin-film transistor substrate,improving manufacture yield rate, and expanding the likelihood of massproduction of the oxide semiconductor thin-film transistor substrate.Further, the etch-stop layer and the passivation layer are formed on thesame layer and the source/drain electrode and the pixel electrode areformed on the same layer so that the number of layers made is reduced byone and one round of photolithographic process (which comprisesoperations of film forming, exposure, development, etching, and peeling)is reduced so as to greatly lower down the manufacture cost and improvemanufacture yield rate.

Based on the description given above, those having ordinary skills ofthe art may easily contemplate various changes and modifications of thetechnical solution and technical ideas of the present invention and allthese changes and modifications are considered within the protectionscope of right for the present invention.

What is claimed is:
 1. A method for manufacturing a thin-film transistorsubstrate, comprising the following steps: (1) providing a substrate;(2) forming a gate terminal having a predetermined structure on thesubstrate; (3) forming a gate insulation layer on the gate terminal andthe substrate; (4) forming a metal signal line having a predeterminedstructure on the gate insulation layer; (5) forming an oxidesemiconductor layer having a predetermined structure on the gateinsulation layer; (6) forming a passivation layer having a predeterminedstructure on the gate insulation layer, the metal signal line, and theoxide semiconductor layer; and (7) forming a source/drain terminalhaving a predetermined structure on the metal signal line, the oxidesemiconductor layer, and the passivation layer so as to form a thin-filmtransistor substrate.
 2. The method for manufacturing the thin-filmtransistor substrate as claimed in claim 1, wherein the substrate is aglass substrate; the oxide semiconductor layer is formed of indiumgallium zinc oxide, indium gallium oxide, zinc oxide, aluminum oxide, ortin oxide.
 3. The method for manufacturing the thin-film transistorsubstrate as claimed in claim 1, wherein in step (6), at the same timewhen the passivation layer is formed, an etch-stop layer having apredetermined structure is also formed, the etch-stop layer beinglocated on the oxide semiconductor layer the passivation layer beingarranged at opposite sides of the etch-stop layer, the passivation layerand the etch-stop layer being made of the same material or differentmaterials.
 4. The method for manufacturing the thin-film transistorsubstrate as claimed in claim 1, wherein in step (7), at the same timewhen the source/drain terminal is formed, a pixel electrode is alsoformed, the pixel electrode being formed on the passivation layer andelectrically connected with the source/drain terminal, the source/drainterminal and the pixel electrode being both formed of transparentconductive oxide.
 5. The method for manufacturing the thin-filmtransistor substrate as claimed in claim 4, wherein the transparentconductive oxide comprises indium tin oxide.
 6. A method formanufacturing a thin-film transistor substrate, comprising the followingsteps: (1) providing a substrate; (2) forming a gate terminal having apredetermined structure on the substrate; (3) forming a gate insulationlayer on the gate terminal and the substrate; (4) forming a metal signalline having a predetermined structure on the gate insulation layer; (5)forming an oxide semiconductor layer having a predetermined structure onthe gate insulation layer; (6) forming a passivation layer having apredetermined structure on the gate insulation layer, the metal signalline, and the oxide semiconductor layer; and (7) forming a source/drainterminal having a predetermined structure on the metal signal line, theoxide semiconductor layer, and the passivation layer so as to form athin-film transistor substrate; wherein in step (6), at the same timewhen the passivation layer is formed, an etch-stop layer having apredetermined structure is also formed, the etch-stop layer beinglocated on the oxide semiconductor layer the passivation layer beingarranged at opposite sides of the etch-stop layer, the passivation layerand the etch-stop layer being made of the same material or differentmaterials.
 7. The method for manufacturing the thin-film transistorsubstrate as claimed in claim 6, wherein the substrate is a glasssubstrate; the oxide semiconductor layer is formed of indium galliumzinc oxide, indium gallium oxide, zinc oxide, aluminum oxide, or tinoxide.
 8. The method for manufacturing the thin-film transistorsubstrate as claimed in claim 6, wherein in step (7), at the same timewhen the source/drain terminal is formed, a pixel electrode is alsoformed, the pixel electrode being formed on the passivation layer andelectrically connected with the source/drain terminal, the source/drainterminal and the pixel electrode being both formed of transparentconductive oxide.
 9. The method for manufacturing the thin-filmtransistor substrate as claimed in claim 8, wherein the transparentconductive oxide comprises indium tin oxide.
 10. A thin-film transistorsubstrate, comprising: a substrate; a gate terminal, which is located onthe substrate; a gate insulation layer, which is located on thesubstrate and the gate terminal; a metal signal line, which is locatedon the gate insulation layer; an oxide semiconductor layer, which islocated on the gate insulation layer and arranged at one side of themetal signal line; a passivation layer, which is located on the gateinsulation layer, the metal signal line, and the oxide semiconductorlayer; a source/drain terminal, which is located on the metal signalline, the oxide semiconductor layer, and the passivation layer, thesource/drain terminal being electrically connected with the metal signalline; and a pixel electrode, which is located on the passivation layerand is in direct contact with the source/drain terminal, and is locatedon the same layer as the source/drain terminal, the source/drainterminal and the pixel electrode being formed of transparent conductiveoxide.
 11. Thin-film transistor substrate as claimed in claim 10,wherein the substrate is a glass substrate.
 12. Thin-film transistorsubstrate as claimed in claim 10, wherein the oxide semiconductor layeris formed of indium gallium zinc oxide, indium gallium oxide, zincoxide, aluminum oxide, or tin oxide.
 13. Thin-film transistor substrateas claimed in claim 10 further comprising an etch-stop layer located onthe oxide semiconductor layer, the etch-stop layer and the passivationlayer being formed at the same time and being made of the same materialor different materials.
 14. Thin-film transistor substrate as claimed inclaim 10, wherein the source/drain terminal and the pixel electrode areformed at the same time, the transparent conductive oxide being indiumtin oxide.